themicah, I agree that we may never know the true algorithm, but I think we can take anecdotal evidence and make some good guesses.

I agree with SchmutzigMSP, most likely why the pax was UG'd and not the OP was that the pax was higher on the WL because that pax was put on the WL before the OP even bought his ticket. The WL is created at the 5 (or 6) day window if not all plats are EUA'd (or at the 3/4 day window if not all GE's are EUA'd, etc). I have confirmed with several elite agents that you are put on the WL when you don't get your EUA when your window runs.

The WL order doesn't change, it's just appended to. So, only if a bunch of plats are added at the same time do the rules of status, fare, time of ticket purchase apply.

I strongly believe that the OLCI time does not change WL status (unless you bought the ticket after the SE EUA window). You are added to the WL when your EUA runs and you do not get it. NOT, when you do OLCI or when you get the EUA status email from NWA. Again, I confirmed this with several elite agents.

Thus, for me if I have not been EUA'd, I will continue to do the OLCI at 2359, 12 hours, 4, hours, etc until I get my EUA. What still is not known is that if NWA releases seats within 24 hours (which they do because I and other FT-ers have snagged these F seats), whether those who have not done OLCI can snag a release over those on the WL who have already done OLCI.